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Solar Permit Cost Calculator (UK)

Free UK solar permit cost calculator. Estimate DNO G98/G99 application, MCS certification, Building Control and inspection fees for domestic and commercial PV.

Solar Permit Cost Calculator

Building Control (usually £0) £0
Plan review £0
DNO G98/G99 application £180
MCS install certificate £140
Total permitting cost
£320
As % of system cost
4.6%
Estimate only — domestic PV is permitted-development under GPDO Class E.

How to use this calculator

Enter your planned system size in kilowatts, choose domestic or commercial, and the calculator returns four itemized line items reflecting UK regulatory reality: Building Control (usually £0 under GPDO Class E for domestic), plan review, DNO G98/G99 application, and MCS install certificate. The total is compared against typical 2026 UK installed cost (£1,750/kW per Solar Energy UK Market Trends Report and MCS Installation Database) to give a percentage. Use it to sanity-check installer quotes — most reputable MCS contractors bundle these into a single line, but if the breakdown looks padded, ask which DNO they are filing under.

What a UK solar permit actually pays for

Unlike the US AHJ model, the UK splits PV regulatory cost into four streams:

  1. Planning permission — almost always £0 because the GPDO Schedule 2 Part 14 makes domestic rooftop PV permitted development. Exceptions: listed buildings (£258 LBC), conservation areas with Article 4 directions, World Heritage Sites, and ground-mounts over 9 m² in residential gardens.
  2. DNO connection under Engineering Recommendation G98 (single inverter, ≤16 A per phase) or G99 (everything else). G98 is a post-install Notification, free. G99 is a pre-install Application requiring a single-line diagram and inverter type-test certificate, fees £80–£300.
  3. MCS install certificate under MIS 3002. The installer must hold MCS accreditation; the per-install certificate is £80–£150 and is mandatory for SEG eligibility and 0% VAT relief.
  4. Building Regulations Part P electrical self-certification, typically via the installer’s NICEIC, NAPIT, or ELECSA Competent Person Scheme registration. Bundled into install fee.

Solar Energy UK’s 2024 Market Trends Report puts total UK soft-cost permitting at roughly 3% of installed price (£200 on a £6,500 4 kW install), one of the lowest in the developed world thanks to GPDO and CPS self-certification.

Cost by DNO and region

DNO G99 application fees as of 2026:

  • National Grid Electricity Distribution (Midlands, South West, South Wales): £150
  • UK Power Networks (London, South East, East): £180
  • Northern Powergrid (Yorkshire, North East): £230
  • SSE Distribution (Southern, Scottish Hydro Electric): £200
  • SP Energy Networks (Manchester, Merseyside, North Wales, Central/South Scotland): £165
  • Electricity North West (North West): £155

Above 50 kW or where local network capacity is constrained (parts of South West, Norfolk, North London under Grid Constraint Notices), DNOs commission a Statement of Works or Construction Cost Estimate (CCE) that can run £600–£2,500 and trigger consumer cost-contributions for transformer upgrades. The Energy Networks Association’s CONNECT direct.energynetworks.org portal centralises G98 notifications across all six GB DNOs.

Commercial and three-phase systems

Commercial PV over 50 kW typically requires:

  • G99 with type-test pack — every inverter model needs G99 Type Test Verification from the manufacturer, listed on the ENA Type Test Register
  • DNO grid study £600–£2,500 depending on Maximum Export Capacity request
  • Building Regulations full plans submission £500–£1,200 for non-domestic or any work affecting load-bearing elements
  • MCS or RECC accreditation (RECC handles non-MCS routes for commercial)
  • CDM 2015 Construction (Design and Management) Regulations notification to HSE for projects over 30 days or 500 person-days

A typical 30 kW commercial rooftop in 2026 pays £800–£1,500 in itemizable permits — roughly 2–3% of the £42,000–£55,000 installed cost benchmark from Solar Energy UK 2024.

Smart Export Guarantee and how permitting interacts

The Smart Export Guarantee (SEG), Ofgem’s replacement for the old Feed-in Tariff, requires the installer to be MCS-certified and the system to have an Ofgem-approved smart-meter capability (export MPAN). Your supplier (Octopus, OVO, EDF, E.ON, British Gas, Bulb, Good Energy, etc.) pays you a per-kWh tariff for exported electricity — see our solar feed-in tariff calculator for current rates. Without a valid MCS certificate the supplier will reject your SEG application, so the £150 MCS fee functionally pays for itself within months at typical 4–15 p/kWh export rates. The 0% VAT relief on ESMs (Energy Saving Materials) under HMRC VAT Notice 708/6 also requires MCS — without it you pay 20% VAT on the whole install.

How to lower your UK permit cost

  • Confirm permitted development before applying for planning — most domestic installs are GPDO Class E
  • Stay under G98 threshold (3.68 kW single-phase, 11 kW three-phase) if you can — free DNO notification instead of paid application
  • Choose a CPS-registered MCS installer — they self-certify Part P, avoiding the £200–£450 Building Notice
  • Bundle EV charging or battery — Solar Together and similar group-buy schemes share permitting overhead across the cohort

Reference standards

UK grid-tied PV must comply with: BS 7671:2018+A2:2022 (IEE Wiring Regulations) including Section 712 (PV systems), Engineering Recommendation G98 or G99 (Energy Networks Association), MCS MIS 3002 (PV installation), Building Regulations Approved Documents Part A (structural), Part P (electrical), Part L (energy efficiency), and BRE Digest 489 (PV in conservation areas). Solar Energy UK’s installer code of practice and the Renewable Energy Consumer Code (RECC) cover consumer-protection requirements. The Government’s response to the Solar Roadmap 2030 commits to maintaining 0% VAT relief on ESMs and exploring further reductions in DNO application timelines.

Frequently asked questions

Do I need planning permission for solar panels in the UK?
For the vast majority of domestic rooftop PV, no. The Town and Country Planning (General Permitted Development) (England) Order 2015, Schedule 2, Part 14 Class A (the GPDO) makes roof-mounted solar permitted development on dwellinghouses provided the array does not project more than 200 mm above the roof slope, does not exceed the height of the highest part of the roof, and is set back at least 1 metre from the eaves on conservation-area properties. Listed buildings, scheduled monuments and properties in World Heritage Sites do require Listed Building Consent and full planning permission — fees vary by local authority but typically £258 LBC. Ground-mount above 9 m² in a residential garden needs full planning.
What does a DNO G98 or G99 application cost?
G98 (for systems up to 16 A per phase, roughly 3.68 kW single-phase or 11 kW three-phase) is a free Notification to your Distribution Network Operator — you simply tell them after install via the ENA Connect Direct portal. G99 (anything larger, or anything requiring pre-approval) requires an Application to Connect and DNOs charge £80–£300: National Grid Electricity Distribution £150, UK Power Networks £180, Northern Powergrid £230, SSE Distribution £200, SP Energy Networks £165, Electricity North West £155. Above 50 kW or where a network study is needed, fees rise to £600–£2,500 depending on local network capacity.
What is MCS certification and is it mandatory?
MCS (Microgeneration Certification Scheme) certification is mandatory if you want to claim the Smart Export Guarantee (SEG) from your supplier, qualify for any local-authority retrofit grant, or sell the property as energy-efficient with confidence. The installer must be MCS-accredited and the installation must be certified to MIS 3002 (PV) at install time. The MCS certificate itself typically costs £80–£150 and is bundled into the installer's quote. Without MCS your SEG application will be refused and the 0% VAT (under the relief running to 31 March 2027) cannot be applied.
Do I need Building Control approval for solar panels?
Building Regulations Part A (structural) and Part P (electrical) apply to every PV install. For roof-mounted PV on a normal pitched roof the structural check is usually a calculation done by the MCS installer — separate Building Control submission is rarely required. Part P notification, however, is mandatory: either the MCS installer is Competent Person Scheme registered (NICEIC, NAPIT, ELECSA) and self-certifies, or you submit a Building Notice to your local authority (£200–£450 depending on council). Listed buildings and any work that affects fire-spread between dwellings or escape routes need full plans submission (£500–£1,200).
How much is a typical full UK solar permit package?
For a standard 4 kW domestic roof-mount in 2026: £0 GPDO planning + £0 G98 DNO notification + £150 MCS certificate + £100–£200 NICEIC Part P self-certification (bundled into installer fee) = effectively £150–£300 of itemizable permit cost, all of which is normally folded into the £6,000–£7,500 total install. For a 10 kW three-phase or commercial system you add £200 DNO G99 plus £400–£800 plan check, typically £800–£1,500 total permitting.

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